Two general types of bicycle trainers are known in the prior art. In one type, the rear wheel of a two-wheeled bicycle is supported on one or more rollers. As a user pedals, the rear wheel rotates, thereby causing the rollers to rotate. While the rolling friction of the bicycle tire against the roller may simulate the actual rolling resistance that a rider would have to overcome if he or she was pedaling the bicycle at the same speed on a level road, wind resistance is not simulated. The horsepower that a bicyclist must generate through the bicycle pedals to overcome wind resistance increases as a cubic function of the rotational speed of the tires. However, the horsepower needed to overcome rolling resistance increases linearly with an increase of the rotational speed of the tires. Therefore, at higher speed, wind resistance becomes the dominating factor that the bicycle rider must overcome in actual riding conditions.
To overcome the limitations of "roller" type trainers, a second type of bicycle training devices has achieved widespread use during the past several years. This newer class of trainers, termed wind load simulators, include a fan assembly in rotational contact with the rear wheel of the bicycle. The fan assembly rotates with the rear wheel, and generates a load that is essentially identical to the load that would be produced by wind resistance if the pedalist were actually riding the bike at a speed corresponding to the rear wheel rotational speed. The best known type of prior wind load simulator includes means for gripping the frame of a bicycle, and a roller/fan assembly positioned beneath the rear wheel of the bicycle, such that the roller/fan assembly is frictionally engaged by the rear wheel. A second known wind load simulator includes means for supporting the bicycle by gripping the frame, and a roller/fan assembly mounted on an arm that in turn is pivotally connected to the bicycle above the rear wheel adjacent the seat, such that the arm can pivot downward until the roller/fan assembly contacts the rear tire.
Although wind load simulators represent a significant breakthrough in bicycle training devices, existing wind load simulator designs have a number of limitations. All types of wind load simulator must grip and support the bicycle such that the bicycle is stable and the rear wheel is suspended above the support surface. In prior devices, the support system has required at least one member that engages the bicycle on one of its painted surfaces, an approach that invariably leads to scratching of the paint and possible damage to the thin tubular frame. A second drawback of existing wind load simulators relates to vibration. In prior simulators, vibration generated by rotation of the fan/roller assembly is directly transmitted to the support surface (i.e., the floor), resulting in low frequency vibrations that can be readily transmitted through floors and walls of a building. This feature places severe constraints on the use of wind load simulators in apartments or similar dwellings. A third limitation of prior wind load simulators is that they have been comparatively bulky devices, not adapted to compact storage and/or transportation.